DeAngelis, Reed T.

BACKGROUND: For reasons not fully understood, Black adults experience more socioeconomic disadvantages (SED) than their White counterparts, as well as earlier onset and greater mortality from heart failure (HF). The John Henryism hypothesis predicts that repeated high-effort coping, that is, John Henryism (JH), with socioeconomic adversity can accelerate cardiovascular aging, thus increasing the risk for HF. METHODS: The analysis sample consisted of participants from the JHS (Jackson Heart Study), a cohort of Black adults from the Jackson, Mississippi Metropolitan area. The analysis sample included participants with no cardiovascular disease at baseline (2000–2004) with complete SED and JH scores. Indicators of SED included low household income, low educational attainment, and low maternal educational attainment scores. JH scores (0–36) were categorized as low (<28), moderate (29–32), and high (>32). Effect moderation of JH in the SED and incident HF association was assessed using interaction terms and stratification. Proportional hazards regression determined the hazard ratio and 95% CI, and models adjusted for age, sex, and established lifestyle risk factors. RESULTS: Among 1704 participants (mean age: 52.15 years, 64.3% female), 100 HF events occurred by 2016 (mean follow-up, 10 years). A statistically significant interaction between income and JH was observed for incident HF ( P =0.04). For every 1-unit increase in income disadvantage score, the risk of HF increased 2-fold among those with high JH (hazard ratio, 2.00 [95% CI, 1.39–2.86]) after full adjustment. Among participants with low JH, the corresponding unadjusted association was hazard ratio, 1.40 [95% CI, 1.04–1.90], but this association attenuated after adjusting for age and sex (hazard ratio, 1.19 [95% CI, 0.87–1.63]). CONCLUSIONS: The association between income disadvantage and HF differed by JH level. Because SED and high JH tend to co-occur, both should be considered in future research aiming to decrease the burden of HF in Black Americans.